import timedef consumer(name):    while True:        print('老子%s准备吃包子啦！'%(name))        baozi = yield        print('老子%s吃了第%s个包子了' %(name,baozi))def producer(name):    print('你爹我%s准备做包子啦！' % name)    a = consumer('xiaoming')    b = consumer('zhangsan')    a.__next__()    b.__next__()    for i in range(1,5):        print('目前总共做了%s包子！' %(i*2))        time.sleep(2)        b.send(i)        a.send(i)producer('tianqiang')